Electric snap-switch.



PATENTED AUG. 23, 1904.

No. 768,474.` l

' N'. MARSHALL.

ELECTRIC SNAP SWITCH.

'2 SHEETS-SHEET l,

APPLIOATION FILED DEO. 24, 1900.

No MODEL.

mw fw PATBNTED AUG. 23,1904.

N. MARSHALL. ELECTRIC SNAP SWITCH.

L A1 PLI0'.4.TI0N FILED Dna. 24,;1900. No MODEL.

2 SHEETS-SHEET 2.

MTN/55555;

UNITED STATES Patented August 23, 1904.

PATENT OFFICE.

SHALL-SANDERS COMPANY, OF B TION OF MAINE.

OSTON, MASSACHUSETTS, A CORPORA- ELECTRIC SNAP-SWITCH.

SPECIFICATION forming part of l Letters Patent N o. '7' 68,474, dated'August 23, 1904. Application flied December 24,1900. serai No. 41,009.(No modelli To @Urol/1,0m t may concern.' Y

Be it known that I, NORMAN MARSHALL, a citizen of the United States,residing at Newton, county of Middlesex, State of Massachusetts, haveinvented anew and usefulElectric Snap-Switch, of which the following isa specification.

My invention relates to electric switches, and more especially tosnap-switches in which the movement of the movable contact is controlledby a plate provided with one or more stops coperating with one or morecatches connected with the movable contact.

Certain features of the invention relate to stop-plates embodied in'thisclass of switches, and the object is to provide a simple and eficientstop-plate which may be conveniently and cheaply manufactured and iswell adapted to production by automatic machinery, whereby theconstruction of the switch is simplified and the cost of productionreduced. To these ends I construct the stop-plate from sheet metal andform the stops thereon by shearing through the metal and bending thesheared portion or portions out of the plane of the body of the plate,thus forming a stop-shoulder either at the end of the bent portion or atthe end of the recess formed in the plate by the offsetting or bendingof the sheared portion.'

The part of the plate thus offset or bent out of the plane of the plateforms a cam-surface on the plate forV preventing backward movement ofthe operating mechanism; as will be more fully explained hereinafter. Astop-plate of this character may be more cheaply manufactured thanstop-plates in which the stop-shoulders or cam-surfaces are formed bymilling or otherwise cutting away the metal, both on account ofthereduction in the waste of the stock and also on account .of theconvenience and rapidity with wh-ich the plates may be produced,especially where automatic machinery is employed in shearing and bendingthe sheet metal and the expense of producing the switches in which theplates are incorporated is consequently reduced. The plates may be cutfrom sheet metal and the plates sheared through an offset or bent by theaction of punches having helical surfaces corresponding in number to thenumber of stop-'shoulders and cam-surfaces to be formed. The catch orcatches which cooperate with the s'top or stops on the'stop-plate may beand prefer-l ably are formed by shearing through a plate of sheet metaland offsetting or bending the sheared portion out of the plane of theplate, the end of the sheared and bent portion or the end of the recessthus forinedin the plate acting as a catch to engage the stop or stopson the stop-plate. By thus forming the catchplate and stop-plate asimple and inexpensive construction is provided for controlling forwardmovement of the movable contact and locking said contact againstbackward movement.

In explaining the invention more fully I will refer to the -followingdrawings, in which- Figure l is a plan View of a double-pole switchembodyingcertain features of the invention in the preferred form. Fig. 2is an elevation of the same, partly in section. Fig. 3 is a sectionalview on line 3 3 of Fig. l. Fig; 4 is a sectional View on line 44 ofFig. l. Fig. 5 is a plan view of the base and cam stop-plate with theother parts removed. Fig. 6 is an elevation of a single-pole switchembodying the features of the invention in their preferred forms,partsof the base being broken away. Fig. 7 is a vertical sectional Viewthrough the center of said'switch, the parts being in the lockedposition and the bindingposts and stationary contacts removed. Fig. 8 isa plan view of the base and cam stop-plate with the other parts removed.Fig. 9 is a plan view of the complete switch. Fig. lO'is a sectionalview showing the lparts in. the moving position. Fig.'11 is a plan viewwith the parts above the catch-plate removed.

In the switch shown Ain Figsl to 5 the parts are supported on aninsulating-base B. The binding-posts I I' I2 I3 are secured to the baseB and support the fixed contacts, which in the form shown consist ofblades forming brushes arranged to eng'age opposite sides of 9 themovable contacts or connector-bars T.,

per end, the disk U is held from rotation by a stop or stops cooperatingwith a catch or catches connected with said disk, and the spring S iswound up or its tension increased until the catches and stops aredisengaged, when the spring acts to suddenly and quickly advance thedisk U and the contacts carried thereby until the advance of the disk isarrested, thereby suddenly engaging or disengaging the movable andstationary contacts. The stop or stops for preventing and arresting theadvance movement of the disk U are formed on a metal plate D, secured tothe base B. This plate is' constructed of sheet metal, and the stops, ofwhich there are four dle with relation to the yoke l'l, thus through theaction of the screw crowding the pins more lirmly down against thecam-surfaces. The cam-surfaces act therefore to prevent any l; ack\\'ardmovement of the spindle or contacts. If the spindle is turned forward,the disk U is held from forward movement by the catches and stops, sothat the spindle turns with relation l'o the disk U and yoke H, and thescrew acts to raise the pins (l in the switch shown, are formed byoffsetting l or bending downward portions of the plate to formgradually-deepening recesses, which terminate in shoulders or stopswhere the metal is sheared through, as at CZ Z2 (Z3 d". The surface ofthe portions of the plate which are thus bent or forced out of the planeof the plate form cam-surfaces the purpose of which will be explainedhereinafter. Instead of forcing or bending portions of the platedownward portions may be offset or bent upward, in 'which case the endof the portion which is sheared through and projects above the body ofthe plate will form a stop and the inclined surface of the portion whichis offset will form a cam-surface. The spindle L is mounted to turn in asleeve or bearing C, secured to the plate D, and the plate is secured tothe base by screws passing through holes formed in ears on the platewhich project into radial recesses extending from the central recess inthe base in which the plate D is located. The catches which cooperatewith the stops on the stop-plate consist of two pins Gr Gr` .extendingthrough holes in the disk U and having' their lower ends arranged toengage the stop-shoulders on the plate D. The en-l in the rear of theshoulders d d, and since longitudinal movement of said pins is preventedby the screw M any attempt to turn the spindle backward tends to turnthe spinuntil the ends are above the catch-shoulders During thismovement of the spindle the tension of the spring S is increased, andwhen the catches are disengaged from the stops the disk U is suddenlyadvanced by said spring. Then thus advanced, the movement of the disk ismore rapid than the moven'ient of the spindle, and in the forwardmovement of the yoke H about the spindle the screw moves the yoke andpins G G downward, so that the ends of the pins bring up against thesucceeding stops (Z2 (,Z and arrest the forward move- :1 ment of thedisk U and contacts T.

On the next forward turning of the spindle the operations are repeated.

Instead of forming a plurality of stops on the stop-plate a single stopand cam-surface j` may be employed if desired, in which case tacts totravel vertically, the catches may be rigidly connected with thecontacts, so that the contacts will partake of the vertical movement ofthe catches.

In Figs. 6 to l1 l have shown a form of single-pole switch in which acam stop-plate is employed embodying the features of in vention referredto and in which the catches are constructed in accordance with certainother features of invention. In this switch the binding-posts I I andthe stationary contacts are similar to those in the double-pole switchdescribed, andthe movable connector or contact-bar H is mounted upon thespindle L lo remain in the same plane. The stop-plate is of the sameconstruction alrady described` with the exception that in this switchthe radially-extemling ears A A are bent downward from the plate andextending through holes in the base, the lower ends of the ears beingengaged by disks or nuts,which bind the plate to the base. The catches,which cooperate with the stop-shoulders on the plate l), are formed byoffsetting or bending downward portions of a catch-plate 1C, the ends ofthe portions which are sheared through forming catches, as at a c ai" a,the number of catches in the form shown correspondingl to the number ofstop-shoulders on the stop-plate. The catch-plate may, however, beprovided with lOO a single catch, if desired', or the stop-plate mayhave a single stop-shoulder to be successively engaged by the catches onthe catchplate.` The catch-plate is screw-threaded at its center toengage the screw-thread M on the spindle, and the catch-plate isconnected with the contact-bar H by means of arms G2, which projectdownward from the bar and eX- tend through recesses N N in the edge ofthe catch-plate, Figs. 10 and 11. The contactbar is provided with a domeJ to lengthen its bearing on the spindle and is connected with thespindle by a'torsional spring S. The general operation of this switch issubstantially the same as the operation already described,

Ythe stop-shoulders and cam-surfaces on the stop-plate cooperating withthe catches on the catch-plate to prevent backward movement of the partsof the switch and to hold the contact-bar from forward vmovement untilthe catch-plate has been lifted by the screw on the spindle to disengagethecatches and stops, when the spring snaps the contact-bar forward,bringing the catches into engagement with the succeeding' stops.

What l claim, and desire to secure by Leti ters Patent, is- Y l. Asnap-switch comprising an insulatingbase provided with a central recess,radial re-A tions thereof offset or bent out of the plane or' the plateto form stop-shoulders and camsurfaces and having ears projecting intosaid radial recesses, a catch for coperating with said stop-shouldersand cam-surfaces, an operating-spindle provided with a screw-thread formoving the catch axially, and a spring connecting said catch andspindle, substantially as described.l

2. Ina snap-switch the combination of an insulating-base, a stop-plateprovided with stop-shoulders, a catch-plate provided with catches forengaging said stop-shoulders, an operating spindle provided with ascrewthread engaging a screw-thread in said catchplate, a contact-barmounted on said spindle above said catch plate and provided withdownwardly-bent portions G2 forming arms,

grooves in thevperiphery of the catch-plate through which said armspass, anda spring connecting said bar and spindle. f

NORMAN MARSHALL.

Witnesses: 4

E. M. BAKER,v L. G. MILTON.

